A facile 3-step synthesis of 5,6-dihydroxyindole (4a) is reported, featuring the Zn(II)-controlled regioselective nitration of 3,4-dihydroxynitrostyrene (2) with tetranitromethane at pH 8.0, and the reductive cyclization of the resulting 4,5-dihydroxy-2,beta-dinitrostyrene (3a) with Na(2)S(2)O(4)/Zn(II) at pH 4. The latter procedure was successfully extended to the conversion of the 2,beta-dinitrostyrenes 3b and 3c to 5,6-dibenzyloxyindole (4b) and 5,6-diacetoxyindole (4c) in good-to-high yields
Expedient synthesis of 5,6-dihydroxyindole and derivatives via an improved Zn(II)-assisted 2,b-dinitrostyrene approach
M. D'ISCHIA;
1999
Abstract
A facile 3-step synthesis of 5,6-dihydroxyindole (4a) is reported, featuring the Zn(II)-controlled regioselective nitration of 3,4-dihydroxynitrostyrene (2) with tetranitromethane at pH 8.0, and the reductive cyclization of the resulting 4,5-dihydroxy-2,beta-dinitrostyrene (3a) with Na(2)S(2)O(4)/Zn(II) at pH 4. The latter procedure was successfully extended to the conversion of the 2,beta-dinitrostyrenes 3b and 3c to 5,6-dibenzyloxyindole (4b) and 5,6-diacetoxyindole (4c) in good-to-high yieldsFile in questo prodotto:
Non ci sono file associati a questo prodotto.
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
